The Learjet broke up and burst into flames during an emergency landing at Lyons-Satolas airport at 2.30pm local time (1.30pm BST). Coulthard, Heidi Wichlinski and Andrew Matthews escaped through a window of the remains of the passenger compartment.

After being taken to hospital by a waiting ambulance, the trio were declared fit. The pilots are understood to have died when the cockpit disintegrated on impact.

The 12-year-old executive jet had been flying from Farnborough in Hampshire to Nice when one of the pilots radioed that he was experiencing engine trouble.

The Scots-born Coulthard, 29, who last night was still expected to compete in this weekend's Spanish Grand Prix despite his brush with death, said he recognised the narrow nature of his escape.

"Obviously I am relieved that Heidi and Andy and myself are unhurt. But I would like to express my sympathy for the families of the two pilots. It's inappropriate for me to go into details of the accident but I am extremely lucky to walk away."

The driver, who races for the McLaren Mercedes Formula One team, helped to pull his fellow passengers from the jet and then called for additional emergency services on his mobile phone.

The dead pilots were named last night as David Saunders, 46, and Dan Worley. Both men worked for Northern Executive Aviation, based in Manchester. Mr Worley, who was in his thirties and had been in the RAF, was awaiting the birth of his second child next month.

The Learjet belonged to David Murray, chairman of Rangers Football Club, and had flown 4,500 hours. It had been chartered from Northern Executive Aviation for the flight to Nice.

Authorities at the Lyons airport refused to speculate on the crash cause but witnesses said the jet hit the ground nose first, destroying the cockpit and nearly splitting the plane in two. Bernard Chaffange, director of the airport, said the rear of the passenger cabin also caught fire before it was put out by fire crews who had raced across the asphalt.

He said: "The plane was on fire at the hind part of the passenger cabin. The fore part of the cabin was totally destroyed. [The passengers] managed to escape the fire immediately.

"They escaped by the window. They managed to get out of the plane themselves immediately after the crash and were picked up in an ambulance and taken to hospital for a check-up. They were in as good a condition as they can be." The trio were discharged from the Edouard-Herriot Hospital in Lyons at 6.20pm local time.

The wreckage was at the side of the runway last night, awaiting examination by air accident investigators. Twisted metal could be seen hanging from the main body of thejet near to where the cockpit had been destroyed. The fire-blackened belly of the fuselage was also visible.

Coulthard was understood to have been travelling to his apartment in Monaco to spend time with Ms Wichlinski, an American fashion model. The driver proposed to her over the new year but the couple have said they do not plan to marry before the end of this racing season. Coulthard's parents, Duncan and Joyce, who run a transport firm in his native Twynholm, Dumfries and Galloway, were on holiday in Spain yesterday.

Coulthard is due to appear before a press conference in Barcelona tomorrow. He is scheduled to race at the Circuit de Catalunya on Sunday.

His victory in the British Grand Prix at Silverstone nine days ago - the seventh win of his six-year Formula One career - lifted him to second place in the drivers' championship, 20 points behind Michael Schumacher of Ferrari.